Field of Invention
The present disclosure relates to a regenerative braking control method of a hybrid vehicle, and more particularly, to a regenerative braking control method of a hybrid vehicle capable of constantly keeping a braking sense during regenerative braking and preventing braking efficiency from reducing.
Description of Related Art
A hybrid vehicle means a vehicle which is driven by efficiently combining two different power sources, and in most cases, means a vehicle which is driven by an engine obtaining a torque by combusting fuel (fossil fuel such as gasoline) and an motor (motor/generator) obtaining a torque by battery power.
The hybrid vehicle has a great potential since it adopts an engine and an electric motor (motor/generator) as an auxiliary power source to be able to reduce exhaust gas and enhance fuel efficiency and a study on the hybrid vehicle has been actively conducted to meet the demands of the times which have to enhance fuel efficiency and develop environmentally-friendly products.
Meanwhile, a recent hybrid vehicle uses a dual clutch transmission (DCT) which may transfer a driving force to a vehicle wheel without interrupting a supply of power from a power source.
The dual clutch transmission is configured to connect a shaft (main shaft) of any one of an odd transmission mechanisms having odd-numbered shift stages (1, 3, 5, 7 stages, and the like) and even transmission mechanisms having even-numbered shift stages (2, 4, and 6) to a motor (motor/generator) side.
The hybrid vehicle in which the dual clutch transmission is equipped uses some of the braking force generated at the time of braking for power generation of the motor to perform a regenerative braking function which uses the generated electric energy to charge the battery.
That is, the regenerative braking is a braking method which uses some of kinetic energy by a driving speed of the vehicle as energy required to drive the motor to generate electric energy while reducing (reducing the driving speed) the kinetic energy.
According to the existing regenerative braking method of a hybrid vehicle, when the shift stage (gear stage) is changed in the transmission mechanism connected to the motor during the regenerative braking, after the torque of the motor is to be “0”, the shifting is performed by a dog clutch, and the like and then the regeneration of the motor is performed, such that the braking sense may vary.
To solve the above disadvantages, when the torque of the motor is “0”, a control method for compensating for a braking force by increasing an oil pressure of a brake or using an engine brake has been used. However, in the case of the control method, kinetic energy is not appropriately recovered during shifting, and as a result, the efficiency of the regenerative braking may be extremely reduced.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.